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<A HREF="intro.html"><FONT COLOR="#FFFFFF">1 Introduction</FONT></A><BR>
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<P><FONT SIZE="5">2.7 Macro Expansion</FONT><BR>
<P>One of the strengths of FunnelWeb is that, when writing
product files, it does not attempt to evaluate any text
expression (e.g. text block, parameter, macro call) in
memory and then write the result
out. Instead, it always writes out what it is expanding
dynamically and directly. This means that you need not
fear defining macros that expand to huge amounts of text and
then calling those macros in other macros, or passing those
huge macros as parameters to other macros. In all cases,
FunnelWeb expands directly to the product file, and there
can be no danger in running out of memory during expansion
(except for running out of stack space and other marginally
used resources in pathological cases).
<P>The only thing to remember in this regard is that
FunnelWeb always stores the entire <I>input</I> file and
all included files, in their entirety in memory, for the
duration of the run.
<P>Here is an example, that illustrates how robust
FunnelWeb is:
<P>
<PRE>
@! FunnelWeb copes well with the following
@! macro definitions. (Providing that it has
@! a little over ten megabytes of memory).
@O@<woppa.txt@>==@{@-
@<Quote@>@(@<Humungeous@>@)@+@}
@$@<Quote@>@(@1@)==@{"@1"@}
@$@<Humungeous@>==@{@-
...Ten Megabytes of Text...
@}
</PRE>
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